Automatic die press



J1me 1964 F. RIIEMENSCHNEIDER ETAL 3,133,978

AUTOMATIC DIE. PRESS Filed May 29, 1962 2 Sheets-Sheet 1 N VE N TORSFRITZ RIEMENSCHNEI nd ROLF RGER Attorney June 1954 F. RIEMENSCHNEIDERETAL 3,138,978

AUTOMATIC DIE PRESS Filed May 29, 1962 2 Sheets-Sheet 2 F i .2 9 "-q 1I6 I9! I a IN VE N TORS FRITZ RIEMENSCHNEIDE d ROLF RGER Attorney UnitedStates Patent 3,138,978 AUTOMATIC DIE PRESS Fritz Riemenschneider,Leverkusen, and Rolf Berger,

Opladen, Germany, assignors to Euniuco Aktiengesellschaft furMaschinenbau, Leverkusen, Germany, a corporation of Germany Filed May29, 1962, Ser. No. 198,499 Claims priority, application Germany June 13,1961 3 Claims. (CI. 7899) Our invention relates to automatic die presseswhich comprise ram means cooperating with a plurality of forging dies inwhich metal slugs are succeedingly forged to a desired final shape, inknown presses of that type ejector means at least partially lift theslugs from the dies after each pressing stroke of the ram and transfermeans move the slugs from die to die between said succeeding forgingoperations.

Known automatic die presses of said type have common driving means forthe press ram and for the said transfer means. This is verydisadvantageous because the slug transfer operation is dynamically andmechanically quite complicated and requires a relatively long timewhereas the proper pressing operation is much simpler and can and infact should be effected quickly to allow the pressing tools to remain incontact with the hot slugs for only the shortest possible time and thusprevent overheating of and damage to the tools and the resultingnecessity for repeated replacements thereof.

To evade the said disadvantage our new automatic die press comprisesseparate and independent driving means for the press ram and for thesaid slug transfer means and it includes first control means actuated bythe ram or its driving means arresting the ram after each pressingstroke and second control means actuated by the slug transfer means ortheir driving means for automatically reactivating the press ram afterthe completion of each slug transfer operation. This improvement permitsto operate the press ram with a speed which is independent of the timerequired for the necessarily slower transfer operation. Additionally thesaid independent driving means permit to incorporate into the drivingmeans for the transfer means a safety clutch to serve as protectionagainst any overload caused for example by slugs occasionally stickingin their die.

The said and other objects of our invention will be more fullyunderstood from the following specification when read with theaccompanying drawing in which one embodiment of our new automatic diepress is illustrated.

In the drawing:

FIG. 1 shows a somewhat diagrammatic longitudinal sectional view of theautomatic die press,

FIG. 2 a similarly more or less diagrammatic cross sectional viewthereof, and

FIG. 3 a kinematic diagram illustrating the operation of the die press.

The automatic die press shown in FIGS. 1 and 2 comprises a machine frame11 guiding a vertically reciprocable ram 13 which is provided with aplurality of equally spaced punches 12, for example three punches 12a,12b, 12c, and is actuated by a pitman 14 and crank shaft 15. This crankshaft is rotated by a not shown motor over the electrically controlledclutch 16. A control disk 17 keyed to the opposite end of said shaft isprovided with a trip cam 18 which actuates an electrical switch 19causing a periodic disengagement of the clutch 16 after each com pleteturn of shaft 15. A periodic reengagement of said clutch 16 is effectedby the electrical switch 47 which is actuated by the trip cam 46 oncontrol disk 45 as will be described in detail hereinafter. The electricmeans are schematically indicated by the switch box 19' and the wirings19" and 47'.

Each of the said punches 12a, 12b, 12c cooperates with one of the dies29a, 20b, 20c, which are mounted in the machine frame and in which slugsare successively forged. After each forging operation the slugs are atleast partially lifted from their respective die by push rods 21 orsimilar lifting means and thereafter each lifted slug is seized by onepair of a plurality of laterally engaging gripping jaws 22 andhorizontally transferred by one spacing of the die. The preheated rawslugs are individually fed in known manner for example by a not shownfeed chain to a re ceiving platform 5%; there each slug is seized by afirst pair gripping jaws 22 and horizontally transferred into the firstdie 20a; after being partially forged therein and lifted therefrom theslug is seized by a second pair of gripping jaws 22a and horizontallytransferred into the second die Ztlb; again, after being further forgedtherein and lifted therefrom the slug is seized by a third pair ofgripping jaws 22b and horizontally transferred into the third die 20c;and after being finally forged therein and lifted therefrom the slug isseized by a lastpair of gripping jaws 22 and horizontally transferredupon a receiving platform 51 from which it is carried off byconventional means such as a not shown transportation chain. It will bewell understood that the said pairs of gripping jaws operateconcurrently and that the preheated slugs may be fed into the first dieand the finally forged slugs removed from the last die in any ofdifferent known manners.

The vertically guided push rods 21 are at their lower ends connected toan up and down moving horizontal beam or other support 23. This up anddown movement is efiected by crank arms 26 keyed upon shaft 27 and bythe slotted levers 24 and link members 25. The two shafts 27 areoperatively connected and synchronized by the cross shaft 28 and thebevel gearings 28. One ofthe shafts 27, namely the one shown in FIG. 2,serves as the principal driving shaft and is continuously propelled byanot shown motor; an interposed friction clutch 29 serves as protectionagainst overloading.

The gripping jaws 22 are elastically mounted on a pair of transfermembers such as beams 30 each of which is slidably guided for up anddown displacement by guide rods 31 fixedly attached to saddles 32. Thesesaddles are. slidably resting upon benches or similar supports 33- andare concurrently displaceable against and from each other as indicatedby the associated arrows 30' shown inFIG. 2. to effect the gripping andreleasing action of the jaws .22. This displacement is effected bymulti-armed levers 34 pivoted at 35 in said supports 33; said levers 34are loaded by spring 36 and prop with rollers 37 againststationary facecams 38.

The supports 33 are displaceable in vertical and horizontal direction byrocker arms 39. These rocker arms are pivoted in sliding blocks 41 whichreciprocate between guide means 4-2 swivelingly mounted upon the machineframe and are actuated by crank arms 40 keyed upon shaft 27.

It will be understood that as supports 33 move in a vertical directionthe cams 38 force rollers 37 in a direc- :9 tion away from each other,and the side arms engaging spring 36 will be rotated to point in adownward direction. In this position spring 35 will bias the levers 34to rotate the same and close the jaws 22 on the workpiece for transfer.After such transfer has been completed the levers 34 are again pivotedby an adjacent set of cams 38 and jaws 22 will be held open by the biasof spring 36.

The said rocker arms 39 impart to the bench members 33 in addition totheir above mentioned displacement in vertical direction a reciprocatinghorizontal movement which is limited by the shoulders 43. To allow thesaid rocker arms 39 the kinematically required freedom of movementrelative to the bench members 33 they engage the latter over interposedpressure springs 44.

The shaft 27 drives over bevel gearing 27 the above mentioned controldisk 45 provided with a trip cam 46 which actuates an electrical switch47 causing a periodic reengagement of the clutch 16 with the crank shaft15.

The operation of our new die press may be best described with referenceto the kinematic diagram of FIG. 3 showing the closed approximatelybeanshaped trajectory k followed by the driving end of rocker arms 39which impart to the bench members 33 the above indicated compositemotion. The following legend lists the meaning of the referencecharacters appearing in FIG. 3:

aamplitude of rocker 39 i--operative movement of the reciprocatingtransfer means rinoperative return movement of the reciprocatingtransfer means scompression of springs 44 after the lateral movement ofbench members 33 has been arrested by shoulders 43 p-pressing and returnstroke of ram 13 G--clutch 16 is engaged by switch 47 to start theoperation of ram 13 Hclutch 16 is disengaged by switch 19 to stop theoperation of ram 13 A-B-closing movement of jaws 22 and seizure of slugsprecedingly lifted from the dies by push rods 11 BClifting of thetransfer means and the jaws with seized slugs C-Dforward movement of thetransfer means and the seized slugs by one spacing of the diesDElowering of transfer means and the jaws with the still seized slugsE-F--opening of jaws and releasing of slugs Let this description startat point A of trajectory k. Shortly before this point has been reachednamely at point H, the punches 12 have completed a pressing operationwithin the respective dies 20 and have been withdrawn therefrom, and thepush rods 21 have lifted the operated on slugs from the dies. The clutch16 has been disengaged by the cam means 17, 13 actuating the switch 19and the ram 13 is arrested in its uppermost position while theuninterruptedly driven shaft 27 continues to rotate. In this position,as illustrated in FIG. 1, the left bench member 33 contacts with itsright flank the shoulder 43 and the two, namely the said left and theright members 33 which are coupled by the transfer beam 35 terminatetheir horizontal return movement r to start a straight upward movementfrom A to B and to C. During the upward movement from A to B the saddles32 and the transfer beams 30, which are slidably mounted on guide rods31 and therefore will not follow said upward movement, approach eachother as explained above and the jaws 22 are caused to grip the slugswhich meanwhile have been lifted from their respective dies by the pushrods 21. When the gripping action is completed at B the rising benchmembers 33 contact the transfer beams 30 and start to lift the same andthe operating jaws mounted thereupon together with the gripped slugs, sothat the slugs will be completely removed from the dies in which theywere precedingly operated on. This lifting movement is completed at Cand the transfer beams 30 with the operating jaws and the slugs heldtherein move thereafter to the left along the tra ectory section CD bythe spacing of the dies so that each slug gripped and lifted from onedie is transferred to above the next following die at D. At this momentthe right bench member 33 was stopped in its horizontal movement by theright shoulder 43 and the two bench members 33 continue to movevertically downward as indicated by the line DE-F. The downward movementof the transfer beams 39 is terminated at E at which point the benchmembers 33 disengage from said beams and continue to move downward fromE to F causing the saddles 32 and thus also the transfer beams 30 tomove away from each other whereby the jaws 22 are opened and thetemporarily held slugs released into the next following dies. At thismoment F the bench members 33 and the transfer beams 30 start theirreturn movement r to the starting position at A.

At point G the trip cam 46 actuates the switch 47 which reengages theclutch 16 to the shaft 15. The shaft 15 is allowed to make an at leastapproximately full turn to effect a press stroke of ram 13 causing thepunches 12a, [2, c, to forge the slugs within the respective dies 2th:b, c. Before the shaft 15 completed said turn, the trip cam 18 operatesthe switch 19 which disengages the clutch 16 and thereby arrests thepress ram 13 in its uppermost position shown in FIG. 1 of the punches12. When point A is reached the operation may be repeated as often asdesired.

It will be well understood that the location of the points G and H maybe varied relative to the points A and F, respectively, and thus theduration of the pressing stroke 7 may be properly chosen. In general,the forging operation should be as quick as possible and the distancebetween points G and H be so small as the drive for the ram 13 willpermit.

While specific embodiments of our invention have been shown anddescribed in detail to illustrate the application of the principles ofour invention, it will be well understood that the same may be otherwiseembodied without departing from such principles and without avoiding thescope of our appended claims.

What we claim as our invention is:

1. In an automatic die press including a reciprocating press ramprovided with a plurality of aligned and equally spaced punches, and thesame plurality of dies in operative relation thereto, the improvementcomprising in combination (a) first driving means reciprocating saidram;

(b) lifting means for at least partially raising slugs from said diesafter each pressing stroke of said ram;

(0) transfer means reciprocable above said dies in the direction oftheir alignment, said transfer means adapted to seize slugs lifted fromthe dies and to transfer the same in a forward movement to the nextfollowing die,

(d) second driving means for said reciprocating transfer means and saidlifting means, said second and said first driving means beingindependent of each other;

(e) first control means actuated by said first driving means to arrestthe press ram in its inoperative position after each return strokefollowing a pressing stroke, and

(1'') second control means actuated by said second driving means toreactivate said first driving means not sooner than at the start of thereturn movement of the transfer means.

2. An automatic die press according to claim 1 comprising (a) anelectrically controlled clutch within the first driving means;

(b) first cam means operated by said first driving means;

(c) a first electric switch actuated by said first cam means fordisengaging the said clutch after each return stroke of the ramfollowing its pressing stroke; (d) second cam means operated by saidsecond driving means; and (e) a second electric switch actuated by saidsecond cam means for reengaging said clutch not sooner than at the startof the return movement of the transfer means. 3. An automatic die pressaccording to claim 1 comprising a safety clutch incorporated into saidsecond driving means.

References Cited in the file of this patent UNITED STATES PATENTSRichard Oct. 4, 1938 Sharp July 10, 1945 Friedman Oct. 19, 1954 HartungMay 19, 1959 Sanford Mar. 5, 1963

1. IN AN AUTOMATIC DIE PRESS INCLUDING A RECIPROCATING PRESS RAMPROVIDED WITH A PLURALITY OF ALIGNED AND EQUALLY SPACED PUNCHES, AND THESAME PLURALITY OF DIES IN OPERATIVE RELATION THERETO, THE IMPROVEMENTCOMPRISING IN COMBINATION (A) FIRST DRIVING MEANS RECIPROCATING SAIDRAM; (B) LIFTING MEANS FOR AT LEAST PARTIALLY RAISING SLUGS FROM SAIDDIES AFTER EACH PRESSING STROKE OF SAID RAM; (C) TRANSFER MEANSRECIPROCABLE ABOVE SAID DIES IN THE DIRECTION OF THEIR ALIGNMENT, SAIDTRANSFER MEANS ADAPTED TO SEIZE SLUGS LIFTED FROM THE DIES AND TOTRANSFER THE SAME IN A FORWARD MOVEMENT TO THE NEXT FOLLOWING DIE,